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I would be grateful If anyone could explain this, we had just arrived and parked up at the Rhegged Centre near Penrith last August, about 20 to 25 of these Birds were going crazy, they were fighting each other for sole rights to each alloy wheel of the various cars parked beside us, and probably waiting for us to leave ours too, this one saw off raids from several claimants, whilst we watched. Was a warm day so don't think the heat from the Discs would have made any difference, perhaps there were loads of dead bugs trapped behind the wheel...any suggestions.